
const middleware1 = async function (req, res, next) {
  console.log('中间件1')
  res.data = 22
  req.body = {a: 1}
  // throw new Error(232323)
  await next()
  console.log(11111)
}

const middleware2 = async function (req, res, next) {
  console.log('异步中间件操作2-begin')
  await pro2()
  await next()
  console.log(22222)
}

const middleware3 = async function (req, res, next) {
  console.log('中间件操作3')
  await next()
  console.log(3333)
}

const middleware4 = async function (req, res, next) {
  console.log('异步中间件操作4-begin')
  await pro()
}
